Fitting agent and method of determining hearing device parameters

Abstract

A fitting agent for a hearing device and related method is disclosed, wherein the fitting agent is configured to initialize a user model comprising a user preference function; obtain a primary test setting for the hearing device; obtain a secondary test setting for the hearing device; present the primary test setting and the secondary test setting to a user; detect a user input of a preferred test setting indicative of a preference for either the primary test setting or the secondary test setting; and update the user model based on hearing device parameters of the preferred test setting, wherein to obtain the secondary test setting comprises: obtain a candidate set of candidate test settings; determine an uncertainty parameter for each candidate test setting; and select the secondary test setting from the candidate set of candidate test settings based on the uncertainty parameters of the candidate test settings.

The invention claimed is: 
     
       1. An apparatus comprising:
 a processing unit configured to:
 obtain a primary test setting, 
 obtain a set of candidate test settings, 
 determine uncertainty parameters respectively for the candidate test settings, wherein the uncertainty parameters relate to user responses and the primary test setting, and 
 select one of the candidate test settings as a secondary test setting based on one or more of the uncertainty parameters of the candidate test settings; 
 
 an output interface configured to provide the primary test setting and the secondary test setting for presentation to a user; and 
 an input interface configured to obtain a user input indicative of a preference for either the primary test setting or the secondary test setting as a preferred test setting; 
 wherein the processing unit is also configured to update a user model based on a hearing device parameter associated with the preferred test setting. 
 
     
     
       2. The apparatus according to  claim 1 , wherein the processing unit is configured to determine the uncertainty parameters respectively for the candidate test settings by applying a predictor for each of the candidate test settings. 
     
     
       3. The apparatus according to  claim 2 , wherein the predictor for each of the candidate test settings is a weighted distribution function. 
     
     
       4. The apparatus according to  claim 1 , wherein the processing unit is configured to select the one of the candidate test settings having the largest uncertainty parameter as the secondary test setting. 
     
     
       5. The apparatus according to  claim 1 , wherein the processing unit is configured to obtain the set of candidate test settings by sampling a posterior distribution. 
     
     
       6. The apparatus according to  claim 1 , wherein the processing unit is configured to determine whether a stopping criterion is satisfied; and
 after a determination that the stopping criterion is satisfied, updating the hearing device based on the updated user model. 
 
     
     
       7. The apparatus according to  claim 6 , wherein the stopping criterion is based on a normalized weighted information divergence. 
     
     
       8. The apparatus according to  claim 7 , wherein the normalized weighted information divergence comprises a Kullback-Leibler (KL) divergence. 
     
     
       9. The apparatus according to  claim 1 , wherein the processing unit is configured to update a predictor based on the hearing device parameter associated with the preferred test setting. 
     
     
       10. The apparatus according to  claim 1 , wherein the set of candidate test settings comprises at least five candidate test settings. 
     
     
       11. The apparatus according to  claim 1 , wherein the user model is based on a first assumption and a second assumption, wherein the first assumption is that the user preference function is a unimodal preference function, and the second assumption is that the user can be uncertain about preference. 
     
     
       12. The apparatus according to  claim 1 , wherein the user preference function ƒ(x,Λ, θ) is given by:
   ƒ( x ,Λ,θ)=−(( x −θ) T Λ( x −θ)) s ,
 
 where x is an M-dimensional vector in a hypercube └0,1┘ M  that represents M hearing device parameters of the hearing device, θ is a maximizing argument of ƒ, Λ is a positive definite M×M scaling matrix characterizing user sensitivity to hearing device parameter changes, wherein M is an integer, and s is a real-valued exponent in a range from 0.01 to 0.99. 
 
     
     
       13. The apparatus according to  claim 1 , wherein the apparatus comprises an electronic device, a server device, the hearing device, or any combination of the foregoing. 
     
     
       14. A method comprising:
 obtaining a user model comprising a user preference function; 
 obtaining a primary test setting for a hearing device; 
 obtaining a secondary test setting for the hearing device, wherein the act of obtaining the secondary test setting comprises:
 obtaining a set of candidate test settings, 
 determining uncertainty parameters respectively for the candidate test settings, wherein the uncertainty parameters relate to user responses and the primary test setting, and 
 selecting one of the candidate test settings as the secondary test setting based on one or more of the uncertainty parameters of the candidate test settings; 
 
 outputting the primary test setting and the secondary test setting for presentation to a user; 
 obtaining a user input of indicative of a preference for either the primary test setting or the secondary test setting as a preferred test setting; and 
 updating the user model based on a hearing device parameter associated with the preferred test setting. 
 
     
     
       15. A fitting agent configured to perform the method of  claim 14 .